Now, a communication interface called HDMI (High-Definition Multimedia Interface) (registered trademark) is being proposed. A communication system (hereinafter referred to as the “HDMI system”) conforming to HDMI standards includes a source apparatus and a sink apparatus. The source apparatus transmits playback video data through an HDMI interface, and the sink apparatus receives the video data transmitted from the source apparatus through the HDMI interface and displays the received video data.
In addition, in the HDMI system, the sink apparatus can control the source apparatus using commands (hereinafter referred to as the “CEC commands”) conforming to CEC (Consumer Electronics Control) standards.
Currently, a technique is known in which a user remotely controls the source apparatus using a remote control for controlling the sink apparatus (PTL 1).